CentOS 7 Docker Build
Docker is a popular platform for developing, shipping, and running applications in containers. CentOS 7 is a Linux distribution known for its stability and long-term support. In this article, we will explore how to build a Docker image using CentOS 7 as the base image.
Prerequisites
Before we start, make sure you have Docker installed on your system. You can download and install Docker from the official website: [Docker Official Website](
Building a Docker Image with CentOS 7
To build a Docker image with CentOS 7, we need to create a Dockerfile. The Dockerfile is a text document that contains all the commands needed to build a Docker image. Here is an example Dockerfile for building an image based on CentOS 7:
# Use the CentOS 7 base image
FROM centos:7
# Set the maintainer information
LABEL maintainer="your_email@example.com"
# Update the package repository and install some packages
RUN yum -y update && \
yum -y install wget curl
# Set the working directory
WORKDIR /app
# Copy files into the container
COPY . /app
# Define the entry point for the container
CMD ["bash"]
Let's break down the Dockerfile:
FROM centos:7
: This line specifies that we want to use the CentOS 7 base image for our Docker image.LABEL maintainer="your_email@example.com"
: This line sets the maintainer information for the image.RUN yum -y update && \ yum -y install wget curl
: This line updates the package repository and installswget
andcurl
packages.WORKDIR /app
: This line sets the working directory inside the container to/app
.COPY . /app
: This line copies the current directory into the/app
directory inside the container.CMD ["bash"]
: This line specifies the default command to run when the container is started.
Building the Docker Image
To build the Docker image, create a directory with the Dockerfile and any other necessary files, then run the following command:
docker build -t my_centos_image .
In this command:
-t my_centos_image
: This flag tags the image with a name (my_centos_image
in this case)..
: This specifies the build context, which is the current directory.
Running the Docker Container
Once the Docker image is built, you can run a container based on that image using the following command:
docker run -it my_centos_image
This command will start a new container based on the my_centos_image
image and open an interactive terminal session inside the container.
Conclusion
In this article, we have learned how to build a Docker image using CentOS 7 as the base image. Dockerfiles are essential for defining the steps needed to build an image, and they provide a reproducible way to create and share containerized applications. Experiment with different packages and configurations in your Dockerfile to customize your images according to your requirements. Happy containerizing!